Recently, many researchers are proposed Fiber-to-the home (FTTH) for area network. Their proposals are based on complementary detection technique. This invention proposed the novel FTTH structures based on the RANDOM DIAGONAL (RD) code in metropolitan area network environment using a newly proposed spectral direct detection technique. One of the important properties of this code is that the cross correlation at data segment is always zero, which means that Phase Intensity Induced Noise (PIIN) is reduced. The results which are obtained mainly from the experimental simulation works are presented. In the simulation analysis, the study will be focused on the point-to-point network using the RD code. The results are taken from the studies on the effect of distance, bit rate, and input power. Finally, the overall FTTH system cost and complexity can be reduced because of the less number of filters used in spectral direct detection technique especially for high number of users.